Answer:
The correct option is;
d(t) = 6·cos(π/3·t) + 28
Step-by-step explanation:
The general form of a cosine function is given as follows;
y = A·cos(B·x - C) + D
Where;
A = The amplitude = The distance from the peak to the midline = 1/2×(Maximum - minimum)
The amplitude = 1/2 × (34 - 22) = 6 inches
B = 2·π/P = 2·π/6 = π/3
P = The period = 6 seconds
C/B = The phase shift
D = The midline = Minimum + Amplitude = 22 + 6 = 28 inches
x = The independent variable
Therefore, to model the function of the wave can be given as follows;
d(t) = 6·cos(π/3·t) + 28
Well, we know the last three numbers are:
3 (ones)
6 (tens)
7 (hundreds)
The next set is:
9 (thousands)
3 (ten thousands)
0 (hundred thousands)
And finally:
6 (millions)
5 (ten millions)
6 (hundred millions)
So we know that 5 is in ten millions.